The present invention relates to a music producing device for music boxes and the like and, more particularly, to a coiled spring winding mechanism in combination with a drive wheel for use in a music producing device for music boxes and the like.
One example of the prior art coiled spring winding mechanism comprises a toothed wheel having a beveled gear provided along the periphery thereof and a recess portion provided in the center thereof, a ratchet tooth being formed on the flat portion of the recess, an outwardly displacable metallic engaging member fitted into the recess, and a coiled spring axle provided through the engaging member and the toothed wheel so that the engaging member is capable of cooperating with the coiled spring axle.
In connection with this device, following drawbacks are pointed out as follows:
One is that when transmitting a power, the engagement between the ratchet tooth and the engaging member becomes unstable because of difficulties in forming the toothed wheel, dimension error of the ratchet, and a trouble between the coiled spring axle and the engaging member. Second, the metallic engaging member will not engage the ratchet teeth if the toothed wheel moves in an axial direction away from the metallic engaging member with. respect to the coiled spring axle. Third is that, when the coiled spring axle revolves, the contacting sound occuring when the engaging member is in engagement with or out of engagement with the ratchet tooth, echoes in a casing for accommodating the coiled spring winding mechanism.
Another prior art device is disclosd in U.S.Pat. No. 3,390,599. This prior art teaches a music producing device for music boxes and the like having a two-part housing which has interconnecting walls grooved to provide bearings for the axles of the drum, driving spring, governer, and associated transmission gears, the drum having cylindrical bearing portions projecting less than the drum pins and being engaged by the two end reeds of the reed plate, and the music box having bevel gears transmitting the force from the driving spring to the drum.